Feed mechanism



Dec. 8, 1964 G. G. Ml-:NKEL 3,160,340

FEED MECHANISM Filed Dec. 18, 1962 3 Sheets-Sheet l .vw Ww kb G. G. MENKEL Dec. 8, 1964 FEED MECHANISM 3 Sheets-Shea?l 2 Filed Dec. 18, 1962 Dec. 8, 1964V G. G. MENKl-:L 3,160,340

FEED MECHANISM Filed Dec. 1s, 1962 s sheets-snee*v s United States Patent 3,160,340 FEED WC 1 Gary G. Mend-rel, Jamaica, NX., assigner to Design Center, Inc., Long Island City, NKY., a corporation of New York Filed Dec. 18, 1962, Ser. No. 245,537

. 3 Claims. (Cl. 226-53) The present invention is concerned with an improvement in machines of this general type and in particular with a novel and improved feeding mechanism for the web of thermoplastic material.

`In the feeding of sheet materials for drawing, it is desirable that the sheet material not be allowed to come loose from the feeding device. This presents a problem in some instances, especially in the case of certain thermoplastic materials such as polarized extruded styrene sheet materials which have a strong tendency to shrink when heated. One example offsuch a material is sold by Plax Corporation under the trademark Polyflex. lt is also desirable that the width of the marginal edges of the sheet material used for gripping the web be as small as possible thereby to afford maximum use of the width of the web for the larticle to be drawn.

It is also desirable that the feed mechanism for sheet material be relatively simple in construction and smooth in operation and that it afford accurate longitudinal registration of the sheet material.

A highly efficient `and desirable feed mechanism for use in machines of this -type is described in United States Patent No. 2,961,137, issued November 22, 1960, to Gary G. Menkel. The feed mechanism of the present invention is an improved mechanism of the class described in the Menkel patent and which overcomes certain problems which have been encountered in the use use of the machine of that patent.

In this regard, the Menkel patent describes the use of an endless thin metal band or strip with a serrated edge for perforating and holding the web. This thin metal band or strip has been found to be subject to breakage, probably due to metal fatigue caused by flexing of the strip as it is moved between the vertical position in which the serrations engage the web and the horizontal position in which it passes around the guide and driving rollers. And while the serrated strip of the Menkel patent has been found to yield superior gripping action as compared with other feed mechanisms, some longitudinal slippage has been experienced on one or both sides of the web, which slippage might be as much as Ma in 18".

In accordance with vthe foregoing, it has been the principal object of the invention to provide a novel and improved feed mechanism for a machine for forming shaped 4articles from sheet materials and particularly heated thermoplastic materials.

Another object of the invention has been the provision of such a feed mechanism which affords an improved web gripping action which prevents release of the web material due to transverse shrinkage stresses and which yields improved longitudinal registration of the advancing web.

A feature of the invention has been the provision of 3,160,340 Patented Dec. 8, 1964 a feed mechanism in which the web is contacted by a thin serrated strip but in which the strip is not subject to fatigue stresses likely to cause breakage due to metal fatigue even over extended periods of use.

Another feature of the invention has been the provision of a feed mechanism of the above type and including an easily adjustable web material guide.

Other and further objects, features and advantages of the invention will appear more fully from the following description of the invention taken in connection with the appended drawings in which:

FIG. 1 is a side elevational View of a machine embodying one form of feed mechanism in accordance with the invention, one side of the machine Ibeing removed for clarity;

FIG. 2 is a plan view of the machine of FIG. 1;

FIG. 3 is a partial cross sectional view taken along the line 3-3 of FIG. l;

FIG. 4 is a partial cross sectional view taken along the line 4 4 of PEG. l;

FIG. 5 is an enlarged side elevational view of a short length of roller chain forming a part of the feed mechanism of FIG. l; and

FIG. 6 is a cross sectional view taken along the 6--6 of FIG. 5.

Referring now to the drawings, there are provided two line ' spaced parallel frame member-s 10 and 11 positioned admechanisms, one for each side of the web 12. Since the l mechanisms are identical, only one will be described in detail, this being the one illustrated in FIG. 1.

The web 12, which may be considered as continuous, is supplied from a reel` 13 vcarried on a shaft 14 journaled for rotation in bearing surfaces provided in standards 15 mounted on the frame members 10 and 11. A series of spaced parallel guide rollers 16, 17, 18, 19 and 20 are mounted on shafts 16', 17, 1S', 19', and 20', respectively, the latter being journaled for rotation in suitable holes provided in the frame members 10 and 11.

On its inside surface the frame member 10 carries an elongated hardened metal strip 21 which has an elongated projection 22 at the top thereof which serves as a lower fixed'guide bar or track. A metal plate 23 is provided Another hardened metal strip 26 is mounted on the inside surface of member 10. The strip 26 is a rectangular in cross section and the bottom surface thereof is located above the tops of plates 23 and 24 and defines, in part, the top of track space 25.

A block 27 is mounted on top of member 10 and one end thereof extends inwardly beyond the inner surface of member 1i) so as to overhang the strip 21. A guide block 23 is suspended beneath block 27 by means of a series of bolts 29 which pass through holes in block 27 and act in' threaded holes 30 in block23. A series of set screws 31 act in threaded holes in block 27 `and press against the upper surface of block 28. The arrangement is such that rota-tion of bolts 29 in an inward threading direction acts to raise block 2S while similar rotation of set screws 31 acts to force block 28 downwards. Thus to raise or lower block 28, opposite rotation of bolts 29 .and set screws 31 is required to raise or lower block 28. motion, block 28 slides along the adjacent surface of strip 26.

The bottom surface of block 23 is provided with an elongated notch 32, the purpose of which will be explained hereinafter. As is best shown in FIG. l, the strips 21 and 26 and the block 2S are parallel .to each other and extend throughout a central portion of frame memberlt). The axialextent of strips 21 and 26 is greater thanl that of block 28.

The under surface of block 2S serves as a guide for an edge portion of web 12 as the latter passes through the upper portion of track space 25. The travel of web 12 commences at reel 13 and continuesV in the direction shown by -arrow 33. The web 12 passes from reel 13 under roller 16, over roller 17, under roller 18, over roller 19 and under roller 20. From roller 20 the web 12 passesfunder a hold down roller 34 which is located above strip 21 adjacent the leading end of the latter. From hold down roller 34, Vthe web 12 passes into the track space 25 and, upon leaving `this space, passes over a laterally disposed ramp or stripper'bar 375.

Y Roller 34 is mounted for rotation on'a stub shaft 36 which passes through a vertically elongated slotk in strip 26 and then through an adjustment block 37, being rigidly attached tothe latter by a nut 38 and bythe end of an Iadjustment screw 39 which extends downwardly into block 37 through a vertical hole 'in the top thereof. The block 37 is mounted in a slot 4@ in frame member 1t) and ,is

`supported from the top of frame-member by means of screw 39 and a yoke 41 which rests on the top of frame member 10. Screw 39 extends upwardly lthrough a hole In its vertical tension; f Idler sprockets 55 and 56 are journaled for rotation on shafts 64 kand 65, respectively, carried on depending brackets 66 and 67,'respectively.

As shown in FIG. 1, thev teeth of sprockets 55 and 56 in contact withroller chain 48 are slightly above the lowermost teethof sprockets 53 and 54 so that return leg 4S of the roller'chain is slightly elevated. This insures good Contact of the roller chain with sprockets 53 and 54.

As web 12 passes from under the roller 21B to under the roller 34, Vthe web is engaged adjacent its marginal edge by teeth 52. The teeth 52, being sharp, cleanly perforate the web 12 so that the web is rmly held by the teeth 32 as the webpasses alongl thetrack space 2,5. The teeth 52, corresponding sets of which are provided adjacent both edges of the web 12, advance the web in an axial direction and positively grip and support the web. The teeth 52 extending into the perforations pre- Y vent slippage or Vshrinkage of the plastic material in Vonto' the teeth 52. Similarly, as shownrin FIGA, the

teeth 52 extend upwardly into slot 32 in guide block 2S so that contact Vbetween the under-surface of guide bar 2S on vopposite sides of slot 32 prevents web 12 from be coming disengaged from teeth 52 during advance through in the top of yoke 41 and is adjustably positioned relative to yoke 41 by means of nuts 42 and 43 acting on opposite sides of yoke 41 anda nut 44 acting against the upper surface of block 37.

By proper adjustment of nuts 42, 43 and 44, the vertical position of block 37 can be altered, thus altering the vertical position of roller 34 and hence the vertical spacing between roller 34 and track 22.r l

The rollerl 34 has a pair ofspaced radial angest45 and 46 between which is provided an annular space 47. The anges 45 and 46 arearranged to be in contact with the web 12 adjacent a marginal edge thereof, as is shown in FIG. 3.

An endless roller chain designated generally by thev Roller chain 48 'passes around sprockets 53 and 54.v

located at opposite ends of the frame 'member 10 and over sprockets 55 and 56 located axially inwardly and below the sprockets 53 and 54, respectively.

The sprocket 53 is mounted forv rotation with a drive shaft 57 journaled .in suitable holes provided in Yframe members 10` andr11. As shownv in FIG. 2, shaft 57 is provided with gears 58 which may be suitably connected to a source of power for rotating shaft 57, sprocket S3 andv the corresponding sprocket 55 provided adjacent frame member 11. Rotation of sprocket 53 causes the roller chains 48 to advance in the direction shown Yby arrows 59 and 60.

Sprocket 54 is mounted for rotation on 11. urged to Vthe left in FIG. l by a spring mechanism 63 in order/tomaintain the roller chain 4Sunder a desired ashaft 61 which is journaled in slots providediin frame members 10 vand A The shaft 61 is contacted by a bushing 62 which is Y track space 25. l

Y The rollers 49 or the roller chain 48 are supported on track 22 throughout the axial length of strip 21. Lateral movement or wobbling of the roller chain is lprevented by plates 23 and 24 which are closely spaced `adjacent opposite` ends of the rollerl chain bearing shafts 49".-

Wobbling of the roller chain is also prevented by contact between kthe tops of the right hand roller chain links 50 (FIGJE) and the bottomsurfaceo hardened strip 26.

The extent of penetration of teeth 52 into the web- 12 Ymay be varied byl changing the vertical position of roller 34 and guide block 23 relative to track 22. Vertical adjustment of roller 34 and guide block 28 also permits easy accommodation of different web thicknesses.

As the web isadvanced through the region in which it is supported between the track 22 and guide bar 28, it may pass first a heating station, generally designated 68, and then a forming station, generally designated 69, where the Ydie contacts the web to form the desired article. The remnant of the web, which represents kwaste material,V is disengaged from the teeth'SZ as the web passes laterally disposed ramp or stripper bar 35.v The advance of the web through the heating and forming zones in an intermittent manner may be controlled in anyconvenient way, such, for example, as is described in the aforementioned Middleton patent.V l Whilevthe invention has been described in connection with a specific embodiment thereof and inra specific use, various modifications thereofrwill occur to those skilled in the art without depart-ing from the spirit and scope of the invention as set forth .in the appended claims.

What is claimed is: n Y

l.A In a machine for forming a thermoplastic sheet material, a feeding mechanism for advancing a web of Vsaid Vmaterial in a predetermined path through said machine whereby desired operations may be performed thereon,

; said feeding mechanism comprising a source of a web of said chain, a pair of support strips each tixedly mounted adjacent a respective edge of said path and each having a roller chain supporting track arranged to guide a respective Yone of said roller chains along said path, said tracks each providing a roller supporting surface with which the rollers of -a respective one of said chains are in rolling Contact as said chains advance along said path, a pair of plates projecting above each of said tracks on opposite sides thereof and arranged to contact opposite sides of said respective roller chains to prevent lateral motion and wobbling thereof, a pair of guide bars each extending longitudinally of said path above a respective roller chain and each being arranged -to contact a respective roller chain adjacent one side thereof, means to guide said web into pressure contact with said teeth whereby said teeth of each roller chain perforate said web adjacent a respect-ive marginal edge thereof, guide means extending longitudinally of said predetermined path and arranged `to contact said web to prevent disengagement of said web from said teeth while said web is passing along said predetermined path, and drive means including a plurality of spaced sprocket wheels for advancing said roller chains along said predetermined path.

2. In a machine for forming a thermoplastic sheet material, a feeding mechanism for advancingv a web of said material in a predetermined path through said machine whereby desired operations may be performed thereon, said feeding mechanism comprising a source of a web of said sheet material, a pair of spaced endless roller chains each having a series of closely spaced, generally triangularly shaped sharp teeth projecting therefrom in a direction normal to the axis of said chain, said teeth being formed as projections on alternate ones of the side plates on one side of each of said roller chains, a pair of support strips each iixedly mounted adjacent a respective edge of said path and each having a roller chain supporting track arranged to guide a respective one of said roller chains along said path, said tracks each providing a roller supporting surface with which the rollers of a respective one of said chains are in rolling contact as said chains advance along said paths, a pair of plates projecting above each of said tracks on opposite sides thereof and arranged to contact opposite sides of said respective roller chains to prevent lateral motion and wobbling thereof, means to guide said web into contact with said teeth whereby said teeth of each roller chain perforate said web adjacent a respective marginal edge thereof, said last mentioned means including a pair of vertically adjustable rollers each arranged to contact a respective marginal edge of said web to force said web into pressure contact with said teeth, vertically adjustable guide means extending longitudinally of said predetermined path and arranged to contact said web to'prevent disengagement of said web from said teeth while said web is passing along said predetermined path, and `drive means including a plurality of spaced sprocket Wheels for advancing said roller chains along said predetermined path.

3. In a machine for forming a thermoplastic sheet material, a feeding mechanism for advancing a web of said material in a predetermined path through said machine whereby desired operations rmay be performed thereon, said feeding mechanism comprising a source of a web of said sheet material, a pair of spaced endless roller chains each having a series of closely spaced, generally triangularly shaped sharp teeth projecting therefrom in a direction normal to the axis of said chain, said teeth being formed as projections on alternate ones of the side plates on one side of each of said roller chains, a pair of support strips each iixedly mounted adjacent a respective edge of said path and each having a roller chain supporting track arranged to guide a respective one of said roller chains along said path, said tracks each providing a roller supporting surface with which the rollers of a respective one of said chains are in rolling contact as said chains advance along said path, a pair of plates projectingl above each of said tracks on opposite sides thereof and arranged to contact opposite sides of said respective roller chains to prevent lateral motion and wobbling thereof, a pair of guide bars each extending longitudinally of said path above a respective roller chain and each being arranged to contact the side plates opposite said side plates of the corresponding roller chain from which said teeth project, means to guide said web into contact with said teeth whereby said teeth of each roller chain perforate said web adjacent a respective marginal edge thereof, said last mentioned means including a pair of vertically adjustable rollers each arranged to contact a respective marginal edge of said web to force said web into pressure contact with said teeth, said adjustable rollers each having an annular slot into which projects the top of the teeth of the corresponding roller chain, vertically adjustable guide members extending longitudinally of said predetermined path and arranged to contact said web to prevent disengagement of said web from said teeth while said web is passing along said predetermined path, said adjustable guide members each having an axially extending slot into which projects the tops of the teeth of the corresponding roller chain, and drive means including a plurality of spaced sprocket wheels for advancing said roller chains along said predetermined path.

Hawley et al. Ian. 6, 1948 Menkel Nov. 22, 1960 

2. IN A MACHINE FOR FORMING A THERMOPLASTIC SHEET MATERIAL, A FEEDING MECHANISM FOR ADVANCING A WEB OF SAID MATERIAL IN A PREDETERMINED PATH THROUGH SAID MACHINE WHEREBY DESIRED OPERATIONS MAY BE PERFORMED THEREON, SAID FEEDING MECHANISM COMPRISING A SOURCE OF A WEB OF SAID SHEET MATERIAL, A PAIR OF SPACED ENDLESS ROLLER CHAINS EACH HAVING A SERIES OF CLOSELY SPACED, GENERALLY TRIANGULARLY SHAPED SHARP TEETH PROJECTING THEREFROM IN A DIRECTION NORMAL TO THE AXIS OF SAID CHAIN, SAID TEETH BEING FORMED AS PROJECTIONS ON ALTERNATE ONES OF THE SIDE PLATES ON ONE SIDE OF EACH OF SAID ROLLER CHAINS, A PAIR OF SUPPORT STRIPS EACH FIXEDLY MOUNTED ADJACENT A RESPECTIVE EDGE OF SAID PATH AND EACH HAVING A ROLLER CHAIN SUPPORTING TRACK ARRANGED TO GUIDE A RESPECTIVE ONE OF SAID ROLLER CHAINS ALONG SAID PATH, SAID TRACK EACH PROVIDING A ROLLER SUPPORTING SURFACE WITH WHICH THE ROLLERS OF A RESPECTIVE ONE OF SAID CHAINS ARE IN ROLLING CONTACT AS SAID CHAINS ADVANCE ALONG SAID PATH, A PAIR OF PLATES PROJECTING ABOVE EACH OF SAID TRACKS ON OPPOSITE SIDES THEREOF AND ARRANGED TO CONTACT OPPOSITE SIDES OF SAID RESPECTIVE ROLLER CHAINS TO PREVENT LATERIAL MOTION AND WOBBLING THEREOF, MEANS TO GUIDE SAID WEB INTO CONTACT WITH SAID TEETH WHEREBY SAID TEETH OF EACH ROLLER CHAIN PERFORATE SAID WEB ADJACENT A RESPECTIVE MARGINAL EDGE THEREOF, SAID LAST MENTIONED MEANS INCLUDING A PAIR OF VERTICALLY ADJUSTABLE ROLLERS EACH ARRANGED TO CONTACT A RESPECTIVE MARGINAL EDGE OF SAID WEB TO FORCE SAID WEB INTO PRESSURE CONTACT WITH SAID TEETH, VERTICALLY ADJUSTABLE GUIDE MEANS EXTENDING LONGITUDINALLY OF SAID PREDETERMINED PATH AND ARRANGED TO CONTACT SAID WEB TO PREVENT DISENGAGEMENT OF SAID WEB FROM SAID TEETH WHILE SAID WEB IS PASSING ALONG SAID PREDETERMINED PATH, AND DRIVE MEANS INCLUDING A PLURALITY OF SPACED SPROCKET WHEELS FOR ADVANCING SAID ROLLER CHAINS ALONG SAID PREDETERMINED PATH. 